20436623406 has 128 divisors (see below), whose sum is σ = 48826437120. Its totient is φ = 6313536000.

The previous prime is 20436623387. The next prime is 20436623461. The reversal of 20436623406 is 60432663402.

20436623406 is a `hidden beast` number, since 20 + 4 + 3 + 6 + 623 + 4 + 0 + 6 = 666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 21046501 + ... + 21047471.

It is an arithmetic number, because the mean of its divisors is an integer number (381456540).

Almost surely, 2^20436623406 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20436623406, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24413218560).

20436623406 is an abundant number, since it is smaller than the sum of its proper divisors (28389813714).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20436623406 is a wasteful number, since it uses less digits than its factorization.

20436623406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1327 (or 1321 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 36.

The spelling of 20436623406 in words is "twenty billion, four hundred thirty-six million, six hundred twenty-three thousand, four hundred six".